Thank you for your question. The short answer about a packaging plan is - probably. Not so much for a marking plan. If you store or ship anything that can be considered ESD susceptible, then you will no doubt use some sort of packaging material or a variety of materials and containers. You need to document what you are using for packaging in your overall ESD Control Program Plan as specified in ANSI/ESD S20.20. As stated in S20.20 Section 8.4, the packaging requirements must be defined and described as stated in ANSI/ESD S541. Within your packaging plan, you need to have documentation that shows that the packaging material used meets the requirements of S541 for inside your protected areas as well as for shipping outside of the protected areas. A revision of S20.20 is being worked on in committee right now and it is likely that the packaging section will have some additional information but not necessarily additional requirements.
Marking is a different issue. You can choose not to have a specific marking plan as stated in S20.20 Section 8.5. However, most companies will rely on the marking that is already on materials like discharge shielding bags and may apply stickers or labels with appropriate marking on other containers. Your control program plan needs to have a statement about how you would handle customer requested packaging and marking - even though no one is asking for anything right now. As time goes on, it is likely that you will be asked to do something special for some customer with regards to packaging and marking.